$url = 'https://stg-api.raudhahpay.com/api/collections/VCdgKyzl/bills?include=product-collections.product';
 

$data = array(
    "due" => "2020-12-19",
    "currency" => "MYR",
    "ref1"=> "RefTest1",
    "ref2"=> "RefTest2",
    "customer" => array (
        "firts_name" => "Ali",
        "last_name" => "Farid",
        "address" => "Perak",
        "email" =>  "ali@abc.com",
        "mobile" =>  "60136282302",
     ),
    "product" => [
        array (
        "title" => "Package3",
        "price" => "10.00",
        "quantity" => "1"
        
     )
    ]
	
);
$payload = json_encode($data);

print_r ($data_string);
$ch=curl_init($url);

curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);

// Set the content type to application/json
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type:application/json'));

// Return response instead of outputting
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

// Execute the POST request
$result = curl_exec($ch);

//curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
//curl_setopt($ch, CURLOPT_POSTFIELDS, array("customer"=>$data_string));
//curl_setopt($ch, CURLOPT_HEADER, true);
//curl_setopt($ch, CURLOPT_HTTPHEADER,
//    array(
//        'Content-Type:application/json',
//        'Content-Length: ' . strlen($data_string)
//    )
//);

//$result = curl_exec($ch);
//curl_close($ch);